Previous laboratory experiments revealed that Vibrio cholerae A1552 biofilms secrete an antiprotozoal factor that prevents Rhynchomonas nasuta from growing and thus prevents grazing losses. The antiprotozoal factor is regulated by the quorum-sensing response regulator, HapR. Here, we investigate whether the antiprotozoal activity is ecologically relevant. Experiments were conducted in the field...

A literature synthesis of phytoplankton growth (m) and grazing (m) rate estimates from dilution experiments reveals that microzooplankton account for most phytoplankton mortality in the oceans, averaging 60e75% of daily phytoplankton production (PP) across a spectrum of open-ocean and coastal systems. For reasonable estimates of gross growth efficiency (GGEZ 30e40%), such impacts imply that sec...

Grazing management plays an important role in the continuous and economicutilization of pastures. Proper grazing management is a main factor for the accumulation ofplant litter which reduces soil erosion and increase the soil permeability to keep moremoisture in the soil. In current study, the effect of three different grazing intensities (low,moderate and high) along with the grazing gradient ...

Since the halophytes species have an important role in such ecosystem balance and they have been grazed by livestock as supplementary forage, the awareness of livestock's desire to grazing and their preference values of these species is of high priority. Regardless of the importance of halophyte species in the livestock feeding in Iran, there is less published research on the livestock grazing ...

Livestock grazing is one of the most important factors influencing the above-ground community composition and structure in a natural grassland ecosystem. Different grazing intensities also have the potential to alter soil C and N storage substantially in grasslands. We conducted a field community study and soil analyses to determine the effects of different grazing intensities on the above-grou...

Vegetation composition and reproduction of vascular plants were studied in relation to seven spatial structures: Betula pendula, Pinus sylvestris, Juniperus communis, Rosa dumalis, dung pats, grazing rejects and grazed patches. Th e study was performed in 14 unfertilized semi-natural pastures, with diff erent grazing intensities, in southcentral Sweden. Vegetation height diff ered between sites...

In spite of overwhelming experimental evidence to the contrary, rotational grazing continues to be promoted and implemented as the only viable grazing strategy. The goals of this synthesis are to 1) reevaluate the complexity, underlying assumptions, and ecological processes of grazed ecosystems, 2) summarize plant and animal production responses to rotational and continuous grazing, 3) characte...

A long-standing hypothesis states that low year-round phytoplankton biomass in the open subarctic Pacific Ocean is maintained by herbivorous grazing. To evaluate the balance between phytoplankton growth and microzooplankton grazing, we carried out seawater dilution experiments at two subarctic Pacific locations in June and September 1987. Pigment-specific phytoplankton growth and grazing rates ...

Soil bacteria play a key role in the ecological and evolutionary responses of agricultural ecosystems. Domestic herbivore grazing is known to influence soil bacterial community. However, the effects of grazing and its major driving factors on soil bacterial community remain unknown for different plant community compositions under increasing grazing intensity. Thus, to investigate soil bacterial...